Add an interface for providing system wide initialization options to the windowing system.

This allows setting up Linux based systems which use multithreaded OpenGL contexts.

src/lib.rs

@@ -37,6 +37,8 @@ extern crate libc;
 extern crate cocoa;
 #[cfg(target_os = "macos")]
 extern crate core_foundation;
+#[cfg(target_os = "linux")]
+extern crate sync;
 
 pub use events::*;